Integrated-inverter electric compressors having an integrated inverter device are used for compressors for air-conditioners installed in hybrid cars, electric cars, etc. Such an integrated-inverter electric compressor is configured such that an inverter accommodating portion (inverter box) is provided on the outer periphery of a housing accommodating an electric motor and a compression mechanism, and an inverter device that converts DC power supplied from a high-voltage power source to AC power and applies the power to the electric motor in the housing via glass-sealed terminals is mounted therein.
A typical inverter device is formed of a power system board connected to a P-N power line, on which are mounted high-voltage electric components, such as a smoothing capacitor (capacitor) and an inductor coil (a common mode coil or a normal mode coil) for reducing current ripple and common mode noise, and a switching circuit composed of semiconductor switching devices, such as IGBTs, the power system board converting DC power to three-phase AC power to apply the power to an electric motor; a control board on which is mounted a control-and-communication circuit, such as a CPU, composed of devices operating at a low voltage, the control board controlling the AC power applied to the electric motor; and the like. These boards are integrated and mounted to the outer periphery of the housing (for example, see PTL 1).
Because integrated-inverter electric compressors for vehicle air-conditioners are mounted in small engine compartments, they are preferably reduced in size and weight as much as possible, and the same is true for inverter devices mounted therein. In order to make the inverter devices compact and to simplify assembly, those in which the power system board and the control board are integrated as a module via a resin module case have been proposed, in which a thin smoothing capacitor, such as a ceramic capacitor or a film capacitor, and a filter capacitor for removing common mode noise, are accommodated in this inverter module (for example, see PTL 2).